1. Field of the Invention
The present invention relates to an apparatus for injecting fuel into an exhaust pipe in order to regenerate a diesel particulate filter of a diesel engine.
2. Description of Related Art
As a technique for regenerating a diesel particulate filter of a diesel engine, there has been well-known a technique for removing, by burning, captured particulate matter by oxidation reaction heat of fuel by injecting fuel into an exhaust pipe.
As a technique relating to such a technique, there has been proposed that in an exhaust pipe fuel injector that injects fuel into an exhaust pipe in order to regenerate a diesel particulate filter of a diesel engine, a branch point is provided on an upstream side (on a fuel supply source side) of an injection nozzle belonging to a supply system of fuel to be injected into the exhaust pipe, and a fuel storage mechanism that stores fuel remaining in the fuel supply system is provided on a branch side (see Japanese Patent Application Laid-open Publication No. 2012-127287).
Although such a conventional technique is an effective technique, when the regeneration of the diesel particulate filter is interrupted in a case in which, for example, a control signal instructing stopping of the regeneration (diesel particulate filter regeneration stopping signal) is generated due to some reason during regeneration processing of the diesel particulate filter, fuel may remain in the supply system of fuel to be injected into the exhaust pipe (fuel supply system), so that there is a concern that the fuel supply system is blocked due to carbonization of the remaining fuel.
Furthermore, it is necessary to provide the branch point and the fuel storage mechanism communicating with the branch point, and hence, there have been a problem in that the constitution of the fuel injection system becomes complicated, resulting in pushing up of a manufacturing cost.
Still further, there is a concern that fuel is carbonized in a region in the vicinity of the branch point and the fuel storage mechanism communicating with the branch point, and the fuel supply system is blocked thereby.